I think it's also partly a reflection on a shift in society as a whole over the past 10 years - I teach at a big university and we call this the "entitlement generation." Everyone seems to think they are entitled to so much that we used to have to work for and considered special rewards or perks or bonuses.

FF programs have now been around for more than 25 years and many people who do not remember or know the days before FF programs existed see them as an entitlement rather than the marketing tool that they are. When the airlines make changes, they feel as if their entitlement is being taken away or reduced.